It is well recognized that being overweight or obese raises many significant health implications. For example, obesity increases the risk of many diseases and health conditions, including: hypertension, dyslipidemia (for example, high total cholesterol or high levels of triglycerides), type 2 diabetes, coronary heart disease, stroke, gallbladder disease, osteoarthritis, sleep apnea and respiratory problems. In addition to the health implications, overweight and obesity have a significant economic impact on the U.S. health care system. Medical costs associated with obesity involve direct and indirect costs. Direct medical costs include preventive, diagnostic and treatment services related to obesity. Indirect costs relate to morbidity and mortality costs, where morbidity costs are defined as the value of income lost from decreased productivity, restricted activity, absenteeism and bed days, and mortality costs are the value of future income lost by premature death.
Conventional approaches to combat obesity have led doctors to surgically modify patients' anatomies in an attempt to reduce consumption by inducing satiety or a “full” feeling in the patient, thereby reducing their desire to eat. Examples include stomach stapling, or gastroplasties, to reduce the volumetric size of the stomach. In addition, two procedures, the Roux-en-Y gastric bypass and the biliopancreatic diversion with duodenal switch (BPD), reduce the size of the stomach and the effective length of intestine available for nutrient absorption. These two procedures reduce the stomach volume and the ability of a patient to consume food. In an attempt to limit nutrient absorption in the digestive tract, at least one company has introduced a sleeve that is implanted in obese patients. U.S. Pat. No. 7,025,791 discloses a bariatric sleeve that is anchored in the stomach and extends through the pylorus and duodenum and beyond the ligament of Treitz. All chyme exiting the stomach is funneled through the sleeve and bypasses the duodenum and proximal jejunum. By directing the chyme through the sleeve, the digestion and absorption process in the duodenum is interrupted because the chyme cannot mix with the fluids in the duodenum. As there is no mixing of bile with the chyme until the jejunum, the absorption of fats and carbohydrates is reduced. However, these conventional methods suffer from a number of limitations including high correction and mortality rates. Also, conventional methods are costly and prone to adaptation by the patient's digestive tract which reduces the effectiveness of the method.
Accordingly there is a need for an implantable weight loss device that is effective in prompting early and prolonged satiety while being minimally invasive and not irritable to patients over time. At the same time, there is a need to provide a weight control device that can be implanted long-term within a patient with an endoscope in a doctor's office, and that does not require a hospital visit. Finally, it would be advantageous to provide treatment methods for combating obesity based upon the weight loss device that forms a partial gastric outlet obstruction in the stomach to prompt early and prolonged satiety and reduce food consumption.